Tom Tango’s Response to something I wrote
Bill said this:
Part of the problem, I believe, comes from trying to measure things from a non-existent center. I don't believe that we can ever successfully measure the defensive contribution to a team by measuring from the center. I think it is philosophically problematic, and I think that it functionally doesn't work. I think that defensive analysis somehow has to establish a "floor" or a "base", and operate from there. I don't think we will make real progress until we do that.
Bill is wrong on this. We have indeed made progress.
If you have an average fielding 3B then you have an average fielding 3B. The center is the average fielding 3B. The problem is when it comes time to compare the average fielding 3B to the average fielding CF and to the average fielding C. We can get there in multiple steps, just not in one step.
We work with what we have, and what we have is in fact an existent center, or 8 centers: the league average at each position. Once that is done, then we can worry about comparing positions. There's a few ways to get there. And indeed, Bill *has* gotten there already with his fielding spectrum. He jumped there in one step. The rest of us took two steps instead of one.
This is how Bill sees the Defense Spectrum, with "position runs saved" values by position:
42 Catcher
36 SS
32 2B
29 CF
25 3B
20 RF
19 LF
13 1B
0 DH
The total for Bill is 216 "runs saved".
This is how I apply the Defense Positional Adjustment, using 0 as the center point (DH is an annoyance, which I can discuss later):
+12.5 C
+7.5 SS
+2.5 2B
+2.5 CF
+2.5 3B
-7.5 RF
-7.5 LF
-12.5 1B
-22.5 DH
Now, watch what happens if I take my numbers and add 22.5 to each:
35 C
30 SS
25 2B
25 CF
25 3B
15 RF
15 LF
10 1B
0 DH
My numbers come out to 180. In order to get it to 216, I will multiply all those numbers by 1.2. This is what we get:
42 C
36 SS
30 2B
30 CF
30 3B
18 RF
18 LF
12 1B
0 DH
That comes out to 216. Now that I converted my numbers onto Bill's scale, let's put those numbers side-by-side for comparison, with Bill's number first, and my number in paren:
42 (42) Catcher
36 (36) SS
32 (30) 2B
29 (30) CF
25 (30) 3B
20 (18) RF
19 (18) LF
13 (12) 1B
0 (0) DH
That is one heckavu agreement for two systems that have nothing to do with each other. Especially for something that Bill said is philosophically problematic and functionally doesn't work. I got to the exact same place that Bill got to by starting with .500 as the centering point. I just did it in two steps. The first step is easy, the .500 step, of only looking at performance INTRAposition. The INTERposition comparison has more art than science to it, and, as you can see above, both Bill and I got to pretty much the same spot anyway.
So, I basically refute Bill's entire thesis, and I have shown that we are actually in agreement on the broad picture.